gistfile1.diff

--- seqlock_atom.ll	2014-01-04 11:47:54.000000000 +0000
+++ seqlock_seq_cst.ll	2014-01-04 11:47:41.000000000 +0000
@@ -17,6 +17,10 @@
 entry:
   %i = alloca i32, align 4
   %local_lock = alloca i32, align 4
+  %.atomictmp = alloca i32, align 4
+  %.atomictmp2 = alloca i32, align 4
+  %.atomictmp3 = alloca i32, align 4
+  %.atomictmp4 = alloca i32, align 4
   store i32 0, i32* %local_lock, align 4
   store i32 1, i32* %i, align 4
   br label %for.cond
@@ -31,21 +35,29 @@
   %1 = load i32* %local_lock, align 4
   %inc = add nsw i32 %1, 1
   store i32 %inc, i32* %local_lock, align 4
-  store atomic i32 %inc, i32* @lock seq_cst, align 4
-  %2 = load i32* %i, align 4
-  store atomic i32 %2, i32* @x1 seq_cst, align 4
+  store i32 %inc, i32* %.atomictmp
+  %2 = load i32* %.atomictmp, align 4
+  store atomic i32 %2, i32* @lock seq_cst, align 4
   %3 = load i32* %i, align 4
-  store atomic i32 %3, i32* @x2 seq_cst, align 4
-  %4 = load i32* %local_lock, align 4
-  %inc2 = add nsw i32 %4, 1
-  store i32 %inc2, i32* %local_lock, align 4
-  store atomic i32 %inc2, i32* @lock seq_cst, align 4
+  store i32 %3, i32* %.atomictmp2
+  %4 = load i32* %.atomictmp2, align 4
+  store atomic i32 %4, i32* @x1 seq_cst, align 4
+  %5 = load i32* %i, align 4
+  store i32 %5, i32* %.atomictmp3
+  %6 = load i32* %.atomictmp3, align 4
+  store atomic i32 %6, i32* @x2 seq_cst, align 4
+  %7 = load i32* %local_lock, align 4
+  %inc5 = add nsw i32 %7, 1
+  store i32 %inc5, i32* %local_lock, align 4
+  store i32 %inc5, i32* %.atomictmp4
+  %8 = load i32* %.atomictmp4, align 4
+  store atomic i32 %8, i32* @lock seq_cst, align 4
   br label %for.inc
 
 for.inc:                                          ; preds = %for.body
-  %5 = load i32* %i, align 4
-  %inc3 = add nsw i32 %5, 1
-  store i32 %inc3, i32* %i, align 4
+  %9 = load i32* %i, align 4
+  %inc6 = add nsw i32 %9, 1
+  store i32 %inc6, i32* %i, align 4
   br label %for.cond
 
 for.end:                                          ; preds = %for.cond
@@ -62,6 +74,10 @@
   %lv1 = alloca i32, align 4
   %lv2 = alloca i32, align 4
   %local_lock = alloca i32, align 4
+  %.atomicdst = alloca i32, align 4
+  %.atomicdst4 = alloca i32, align 4
+  %.atomicdst5 = alloca i32, align 4
+  %.atomicdst6 = alloca i32, align 4
   %.compoundliteral = alloca [1 x %struct.timespec], align 4
   store i32 0, i32* %v1, align 4
   store i32 0, i32* %v2, align 4
@@ -81,10 +97,12 @@
   br label %while.body3
 
 while.body3:                                      ; preds = %while.body, %if.then, %if.end10
-  %atomic-load = load atomic i32* @lock seq_cst, align 4
-  store i32 %atomic-load, i32* %local_lock, align 4
-  %2 = load i32* %local_lock, align 4
-  %and = and i32 %2, 1
+  %2 = load atomic i32* @lock seq_cst, align 4
+  store i32 %2, i32* %.atomicdst, align 4
+  %3 = load i32* %.atomicdst, align 4
+  store i32 %3, i32* %local_lock, align 4
+  %4 = load i32* %local_lock, align 4
+  %and = and i32 %4, 1
   %tobool = icmp ne i32 %and, 0
   br i1 %tobool, label %if.then, label %if.end
 
@@ -92,13 +110,19 @@
   br label %while.body3
 
 if.end:                                           ; preds = %while.body3
-  %atomic-load4 = load atomic i32* @x1 seq_cst, align 4
-  store i32 %atomic-load4, i32* %v1, align 4
-  %atomic-load5 = load atomic i32* @x2 seq_cst, align 4
-  store i32 %atomic-load5, i32* %v2, align 4
-  %3 = load i32* %local_lock, align 4
-  %atomic-load6 = load atomic i32* @lock seq_cst, align 4
-  %cmp7 = icmp eq i32 %3, %atomic-load6
+  %5 = load atomic i32* @x1 seq_cst, align 4
+  store i32 %5, i32* %.atomicdst4, align 4
+  %6 = load i32* %.atomicdst4, align 4
+  store i32 %6, i32* %v1, align 4
+  %7 = load atomic i32* @x2 seq_cst, align 4
+  store i32 %7, i32* %.atomicdst5, align 4
+  %8 = load i32* %.atomicdst5, align 4
+  store i32 %8, i32* %v2, align 4
+  %9 = load i32* %local_lock, align 4
+  %10 = load atomic i32* @lock seq_cst, align 4
+  store i32 %10, i32* %.atomicdst6, align 4
+  %11 = load i32* %.atomicdst6, align 4
+  %cmp7 = icmp eq i32 %9, %11
   br i1 %cmp7, label %if.then9, label %if.end10
 
 if.then9:                                         ; preds = %if.end
@@ -108,9 +132,9 @@
   br label %while.body3
 
 while.end:                                        ; preds = %if.then9
-  %4 = load i32* %v1, align 4
-  %5 = load i32* %v2, align 4
-  %cmp11 = icmp eq i32 %4, %5
+  %12 = load i32* %v1, align 4
+  %13 = load i32* %v2, align 4
+  %cmp11 = icmp eq i32 %12, %13
   br i1 %cmp11, label %cond.true, label %cond.false
 
 cond.true:                                        ; preds = %while.end
@@ -122,7 +146,7 @@
                                                   ; No predecessors!
   br label %cond.end
 
-cond.end:                                         ; preds = %6, %cond.true
+cond.end:                                         ; preds = %14, %cond.true
   %arrayinit.begin = getelementptr inbounds [1 x %struct.timespec]* %.compoundliteral, i32 0, i32 0
   %tv_sec = getelementptr inbounds %struct.timespec* %arrayinit.begin, i32 0, i32 0
   store i32 0, i32* %tv_sec, align 4